I like the BRS 2 part kit (15% off through today) I've found their dosing pumps to be solid, and their dry mixes are easy to figure out. I eventually went to the Apex Dos, which is very precise and probably easier to setup. But you still have to mix all the dry powders to make the solutions for Cal, Alk, and Mag. I think I started with the B-ionic solutions, which were premixed, just fill with RO water. But the BRS was cheaper and their powders are easy enough to figure out.